1. Field of the Invention
This invention relates to oil soluble hydroxyl terminated additives useful in fuel and lubricating oil compositions, including concentrates containing said additives, and methods for their manufacture and use. The hydroxyl terminated additives are poly(C.sub.5 -C.sub.9 lactone) adducts which have been prepared by reacting a C.sub.5 -C.sub.9 lactone with a polyalkylene amine having a number average molecular weight of from about 300 to about 10,000. The hydroxyl terminated products are effective as dispersants and HD additives.
2. Prior Art
Polyalkylene amines are well known lubricating additives. These agents act to keep sludge and varnish dispersed in engine oils and have been successful commercially.
It is also known that polymers of 6 to 10 membered lactones such as valerolactone or E-caprolactone can be prepared by reacting the lactone monomer with a hydroxyl or amine initiator. When reacting E-caprolactone, for example, the polymerization reaction may be illustrated by the following equations: ##STR1##
The reactions are known to be catalyzed by various esterification catalysts such as stannous octanoate, and a variety of different molecular weight products are feasible depending upon the ratio of lactone to initiator. Molecular weights on the order of from a few hundred up to about 5,000 are reproducably achievable.
Caprolactone can also be polymerized to a very high molecular weight, e.g., on the order of 100,000 or more. Typically such high molecular weight polymers do not employ initiators and preservation of functionality is not a requirement.
It is also known to react a lactone such as E-caprolactone with a diamine wherein one of the amine groups is a tertiary amine and the other amine group is a primary or secondary amine to form a polymer having a terminal hydroxyl group and a terminal tertiary amine group. The polymeric products are useful for neutralizing polymeric acids.
It has now been found that improved oil soluble dispersant additives, useful in fuel and lubricating oil compositions, including concentrates containing the additives, can be prepared by reacting a 6 to 10 membered lactone with a polyalkylene amine, such as a polyisobutylene amine, having a number average molecular weight on the order of about 300 to about 10,000.
While there are a number of prior art disclosures relating to adducts of lactones and polyamines, to polyalkenyl amine lubricating additives and to lactone polymerization reactions, in general, little or no prior art of direct pertinence appears to have surfaced in regard to the present dispersants. Exemplary of the patent literature which relates to lactone polymerization processes and/or to oil soluble dispersant additives are the following U.S. Patents: U.S. Pat. No. 4,362,635 discloses synthetic ester oils which are esterification products of monoalcohols and dicarboxylic acids or of polyhydric alcohols and monocarboxylic acids respectively, containing 5 to 45% by weight of units of hydroxycarboxylic acids obtained from aliphatic alcohols, aliphatic, cycloaliphatic or aromatic carboxylic acids, and lactones of aliphatic C.sub.5 -C.sub.12 hydrocarboxylic acids. The synthetic ester oils are suitable for the preparation of lubricants and lubricant compositions.
U.S. Pat. No. 2,890,208 discloses a process for polymerizing lactones to form lactone polyesters that are useful as plasticizers.
U.S. Pat. No. 2,898,301 discloses alkyl hydroxyamide lubricating fluid additives derived from monoamines, including polymerized fatty acid amines, and gamma-lactones such as gamma-butyrolactone.
U.S. Pat. No. 4,168,278 discloses adducts of primary amines, especially hydroxy amines, and caprolactam. The adducts are useful as depolymerization inhibitors. A similar disclosure is contained in U.S. Pat. No. 3,892,806, which relates to polycaprolactam adducts that are formed by reaction between an N-alkyl alkylene diamine and caprolactam. The adducts are useful as antimicrobial agents.
U.S. Pat. No. 3,832,367 discloses alkoxylated hydroxyamide detergents which are prepared by reacting a beta, gamma, delta or epsilon type C.sub.8 -C.sub.40 lactone with an alkanolamide to form an intermediate hydroxyalkanolamide, and then reacting the intermediate hydroxyalkanolamide with an alkylene oxide.
U.S. Pat. No. 3,373,112 discloses lubricant additives derived from polyalkylene polyamines, including polyisobutylene polyamines and non-lactone acylating agents.
U.S. Pat. No. 3,062,631 discloses condensation products of beta-lactones, particularly C.sub.3 -C.sub.6 betalactones, and amines as corrosion inhibiting additives.
U.S. Pat. No. 3,169,945 discloses the preparation of lactone polyesters which are useful as plasticizers and as intermediates for preparing elastomers and foams. The polyesters can be prepared by reacting a lactone such as E-caprolactone with an initiator such as an alcohol, amine or amino alcohol. A similar disclosure is contained in U.S. Pat. No. 3,284,417. This latter patent also discloses the use of a stannous octanoate polymerization catalyst
U.S. Pat. No. 4,379,914 and its continuation-in-part (U.S. Pat. No. 4,463,168) disclose the preparation of polycaprolactone polymers by reacting E-caprolactone with a diamine wherein one of the amine groups of the diamine is a tertiary amine and the other is a primary or secondary amine. The polycaprolactone polymers are disclosed as being useful for neutralizing certain sulfonic acid-containing polymers to form amine-neutralized, sulfonated derivatives which can be combined with an alkyl benzene sulfonic acid to give a surfactant which contains ester groups, hydroxyl groups and amine-neutralized sulfonate groups.
U.S. Pat. No. 3,436,463 discloses N-substituted gamma hydroxycarboxylic acid amides which are useful as nematocides and insecticides. The compounds of this patent are prepared by reacting an organic primary amine with a lactone such as gamma-butyrolactone or gamma-valerolactone.
U.S. Pat. No. 4,397,750 teaches the preparation of hydroxy substituted pyrrolidone esters from butyrolactones and polyhydroxyamines. Corresponding hydroxyamide side-products are also disclosed. The disclosed esters are useful as additives for lubricants and fuels.
U.S. Pat. No. 3,493,568 discloses diol amides prepared from caprolactone and a monohydroxy amino alcohol. The diol amides can be cyclodehydrated to form oxazolines and oxazines which can be polymerized to yield crosslinked polymeric structures.
U.S. Pat. No. 4,512,903 discloses lubricant compositions containing amides of lactones, such as beta-propiolactone or gamma-butyrolactone, and fatty amines.
U.S. Pat. No. 4,234,435 discloses as oil additives, polyalkylene substituted dicarboxylic acids derived from poly-alkylenes having a M.sub.n of 1300 to 5000 and containing at least 1.3 dicarboxylic acid groups per polyalkylene. In Example 34 of that patent, a polyisobutene-substituted succinic acylating agent is reacted with caprolactam in the presence of mineral oil and sodium hydroxide. That patent also discloses lubricant additives derived from high molecular weight hydrocarbyl amines. The hydrocarbyl amines can prepared by reacting a chlorinated polyolefin having a molecular weight of at least about 400 with ammonia or an amine.
U.S. Pat. No. 3,381,022 relates to ester derivatives of substantially saturated polymerized olefin-substituted succinic acid wherein the polymerized olefin substitutuent contains at least about 50 aliphatic carbon atoms and has a molecular weight of about 700 to 5,000. The esters include the acidic esters, diesters, and metal salt esters wherein the ester moiety is derived from monohydric and polyhydric alcohols, phenols and naphthols. The ester derivatives are useful as additives in lubricating compositions, fuels, hydrocarbon oils and power transmission fluids. A related patent, i.e., U.S. Pat. No. 3,522,179, discloses lubricating compositions comprising a major amount of a lubricating oil and a minor proportion of an ester derivative of a hydrocarbon-substituted succinic acid sufficient to improve the detergency of the lubricating composition. The ester derivatives are similar to those described in U.S. Pat. No. 3,381,022 and contain at least about 50 aliphatic carbon atoms. The hydrocarbon substituent may be derived from a polymerized lower monoolefin having a molecular weight of from about 700 to about 5,000.
All of the above discussed patents are expressly incorporated herein by reference in their entirety.
Additional exemplary prior art disclosures, which are expressly incorporated herein by reference in their entirety include U.S. Pat. Nos. 3,025,323; 4,062,786; 4,086,294; 4,247,671; 4,261,871; 4,292,184; and 4,448,905.